Location-aided RAKE receiver finger assignment

We propose and analyze a new technique for improving RAKE receivers for DS-CDMA systems that eliminates the loss due to incorrect finger assignment. Such loss occurs due to errors caused by the searcher in estimating the average power of multipaths. Our technique uses a mobile location indexed database of multipath delays and average powers obtained error-free through offline techniques. During a mobile call, the mobile location is used to look up the database and obtain error-free finger assignment information. We analyze the improvement due to such a "genie"-aided scheme on the performance of the RAKE receiver in terms of the SNR required to achieve a target BER and in terms of the system user capacity under a 4-path Rayleigh fading scenario.

[1]  P. E. Green,et al.  A Communication Technique for Multipath Channels , 1958, Proceedings of the IRE.

[2]  Laurence B. Milstein,et al.  Acquisition of direct sequence spread spectrum signals with correlated fading , 2001, IEEE J. Sel. Areas Commun..

[3]  S. J. Papantoniou.  A multipath channel model for mobile-radio communications , 1992, [1992 Proceedings] The Third IEEE International Symposium on Personal, Indoor and Mobile Radio Communications.

[4]  Gordon L. Stuber,et al.  Principles of Mobile Communication , 1996 .

[5]  Juha-Pekka Makela,et al.  Indoor geolocation science and technology , 2002, IEEE Commun. Mag..

[6]  Gert Frølund Pedersen,et al.  COST 231 - Digital Mobile Radio Towards Future generation Systems , 1999 .

[7]  Stefan Parkvall,et al.  DS-CDMA Synchronization in Time-Varying Fading Channels , 1996, IEEE J. Sel. Areas Commun..

[8]  R. Clarke.  A statistical theory of mobile-radio reception , 1968 .

[9]  K. Pahlavan,et al.  On the modeling of fading multipath indoor radio channels , 1989, IEEE Global Telecommunications Conference, 1989, and Exhibition. 'Communications Technology for the 1990s and Beyond.

[10]  A. Viterbi.  CDMA: Principles of Spread Spectrum Communication , 1995 .